This invention relates generally to improvements in so-called front end loaders of the type having an hydraulically operated frame for supporting and manipulating a bucket or scoop or other work attachment at the front of the vehicle. More specifically, this invention relates to improvements in work attachments for use with a front end loader, particularly with respect a multipurpose work attachment adapted for performing a multitude of different tasks. The invention is particularly suited for use with relatively small so-called skid-steer front end loaders of the general type described in U.S. Pat. Nos. 3,231,117 and 3,672,521.
Front end loaders are generally known in the art for use in performing a wide range of grading, digging, construction, and other related tasks. In general terms, the front end loader typically comprises a tractor-type vehicle equipped with a pivoting frame having a selected work attachment such as a scoop or bucket connected thereto. Hydraulic actuator units are provided on the vehicle for controlled raising and lowering of the pivoting frame, in combination with controlled fore-aft pitch adjustment of the work attachment. Appropriate manipulation of the hydraulic actuater units enables the work attachment to be correspondingly manipulated to perform a specific desired task.
An exemplary front end loader is shown and described in U.S. Pat. No. 3,231,117, generally in conformance with so-called skid-steer front end loaders marketed by Melroe Company, Division of Clark Equipment Co., Fargo, North Dakota, under the trademark BOBCAT. Such front end loaders are adapted for relatively rapid and interchangeable mounting of different work attachments, such as scoops or buckets, dozer blades, fork lift apparatus, rotary sweepers, jackhammer and auger devices, etc. In this regard, front end loaders of this type are frequently equipped with an adapter mounting plate of type described in U.S. Pat. No. 3,672,521 to facilitate rapid interchanging of work attachments. U.S. Pat. No. 5,403,144 describes an improved adapter mounting plate for controlled lateral tilt adjustment of the work attachment, such as a bucket or scoop, mounted thereto.
In the past, work attachments for front end loaders have generally been designed to perform one or a small number of specific or related tasks. When it is desired to use the front end loader to perform a task of significantly different character, it has been necessary to remove the work attachment presently in use, and to replaced that work attachment with a different one better suited to the new task. For example, a bucket or scoop must removed from the front end loader and replace by a different work attachment, such as a fork lift unit, in accordance with the new task to be performed. Although interchange of work attachments is not necessarily a complicated procedure, at least some time is required to effect the attachment interchange, resulting in a time interval when the front end loader cannot be used to perform a desired work activity.
The present invention is directed to an improved work attachment designed for multipurpose functions and further adapted for rapid mounting of auxiliary attachment devices for the performance of still further work activities.